Test switches facilitate maintenance and troubleshooting for protective relays and other electrical devices. In a typical installation, the test switches are located between the system sensors and protective relays, as part of the high-voltage system. After system sensors such as current and voltage transformers reduce the magnitude of the current and voltage of the system to values that the test switches can utilize, the test switches further route the energy sources in an electrical installation.
Technicians require access to the front and/or rear panels of the test switches to perform maintenance as well as troubleshoot during fault events occurring on the system. However, safely accessing the test switch panel necessitates the technician determining the energized status of the conductors in the switch and the multiple power sources before beginning work.